The present invention relates generally to the field of communications, and more specifically, to communications over a dispersive channel with multiple receiver antennas.
The communication channel between a transmitter and a receiver may be time varying and dispersive. The dispersion of the channel may result in multipath and inter-symbol interference (ISI) and a receiver may need special processing to counteract these and possibly other time varying effects. Such a receiver may include an equalizer for reducing the effect of multipath interference and ISI.
To this end as well as others, there is a need for an effective equalizer in a communication system.
A communication receiver performs signal equalization by minimizing a combined local and global mean square error (MSE). A receiver may include a plurality of antennas for receiving a plurality of signals transmitted from a common source. The plurality of signals carry a common stream of data symbols. A pre-processing block processes the received signals to produce a plurality of processed received signals. In local optimization, the temporal coefficients for the signals from different antenna are optimized based solely on minimizing the MSE between the transmitted symbol and the local estimate of the transmitted symbol. In Global Optimization, the temporal coefficients and spatial combiner weights for signals from all antennas are optimized jointly to minimize the global MSE. A signal equalizer minimizes a combined local and global MSE over the processed received signals to produce a combined signal. A decoder decodes the combined signal to retrieve the stream of data symbols. A processor is configured for combining a local MSE and a global MSE in accordance with a weighting factor xcex1 to produce the combined local and global MSE. The processor is configured for adjusting the weighting factor a to achieve a corresponding effect of adaptation speed and error magnitude in minimizing the combined local and global the MSE.